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In the northeastern tropical Atlantic, a region of high potential vorticity (PV) determines the size of the exchange window for the interior thermocline flow of the subtropical cell via its variations in strength and extent. Variability of this PV barrier has the potential to impact the ventilation of the tropical Atlantic on decadal timescales. Here, the impact of the North Atlantic Oscillation (NAO) on the PV barrier related to isopycnals within the thermocline of the subtropical‐tropical Atlantic Ocean is assessed from Argo observations for the time period of 2006–2022. Relative to the negative NAO phase (2009–2010), during the positive NAO phase (2014–2019), the North Atlantic subtropical high and the northeast trades are intensified. Satellite‐derived wind stress curl shows increased upwelling/downwelling on the equatorward/poleward side of the trade wind zone, respectively. In the subtropical‐tropical Atlantic, a symmetric pattern of isopycnal heave is observed: rising isopycnals within 20°N and 20°S and sinking poleward of that. With rising isopycnals, the PV barrier in the northeastern tropical Atlantic becomes stronger. Analyses of geostrophic velocities and the Sverdrup streamfunction show that during the positive NAO phase there are increased equatorward velocities at thermocline level along the western boundary and reduced velocities through the interior as a result of intensified northeast trades and therefore a strengthened PV barrier. Intensified trades lead to enhanced subduction of thermocline waters and, independent of that, to a strengthened Equatorial Undercurrent transport as observed at the mooring site at 0°, 23°W, likely via the pulling effect of the subtropical cells. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to evaluate the dosimetric impact on hypofractionated prostate radiation therapy of two geometric uncertainty sources: rectum and bladder filling and intrafractional prostate motion. Materials and methods: This prospective study included 544 images (375 pre-treatment cone-beam CT [CBCT] and 169 post-treatment CBCT) from 15 prostate adenocarcinoma patients. We recalculated the dose on each pre-treatment CBCT once the positioning errors were corrected. We also recalculated two dose distributions on each post-treatment CBCT, either using or not intrafractional motion correction. A correlation analysis was performed between CBCT-based dose and rectum and bladder filling as well as intrafraction prostate displacements. Results: No significant differences were found between administered and planned rectal doses. However, we observed an increase in bladder dose due to a lower bladder filling in 66% of treatment fractions. These differences were reduced at the end of the fraction since the lower bladder volume was compensated by the filling during the treatment session. A statistically significant reduction in target volume coverage was observed in 27% of treatment sessions and was correlated with intrafractional prostate motion in sagittal plane > 4 mm. Conclusions: A better control of bladder filling is recommended to minimize the number of fractions in which the bladder volume is lower than planned. Fiducial mark tracking with a displacement threshold of 5 mm in any direction is recommended to ensure that the prescribed dose criteria are met. [ABSTRACT FROM AUTHOR]

The requirement of high memory bandwidth for next-generation computing systems moved the attention to the development of devices that can combine storage and logic capabilities. Domain wall-based spintronic devices intrinsically combine both these requirements making them suitable both for non-volatile storage and computation. Co\Pt and Co\Ni were the technology drivers of perpendicular Nano Magnetic Logic devices (pNML), but for power constraints and depinning fields, novel CoFeB\MgO layers appear more promising. In this paper, we investigate the Ta2\CoFeB1\MgO2\Ta3 stack at the simulation and experimental level, to show its potential for the next generation of magnetic logic devices. The micromagnetic simulations are used to support the experiments. We focus, first, at the experimental level measuring the switching field distribution of patterned magnetic islands, Ms via VSM and the domain wall speed on magnetic nanowires. Then, at the simulation level, we focus on the magnetostatic analysis of magnetic islands quantifying the stray field that can be achieved with different layout topologies. Our results show that the achieved coupling is strong enough to realize logic computation with magnetic islands, moving a step forward in the direction of low power perpendicularly magnetized logic devices. [ABSTRACT FROM AUTHOR]

Atmospheric physics is represented in numerical models by parameterizations that use resolved‐scale information to estimate the effects of physical processes on the atmospheric state. Over time, our understanding of these processes improves, new techniques are introduced to represent physics in a numerical model, and increased resolution changes the relative importance of different parameterizations within the system. As a result, the physical parameterization packages of numerical weather prediction (NWP) models undergo regular updates as older schemes are replaced with newer ones that offer an improved, and often more complex, depiction of relevant physical processes. Such changes are typically combined with a rebalancing of the physics suite because of strong interactions between parameterization schemes and the presence of compensating errors in the system. In this study, a major update to the package of physical parameterizations used in Canadian operational NWP is introduced. The primary goals of this effort were to improve the global energy budget and to facilitate an increase in the vertical resolution of operational configurations. Both of these objectives were achieved, along with a significant improvement in guidance quality for global and regional prediction systems. Key Points: An updated suite of parameterizations for atmospheric physics is developed for Canadian NWPRepresentation of the global energy budget is improved in the model climatologySignificant improvements in guidance quality are seen in upper‐air, surface, and precipitation scores [ABSTRACT FROM AUTHOR]

Background: The objective was to determine the magnitude of the prostate intrafractional motion relative to bony pelvis anatomy, and to evaluate the relationship between this displacement and some clinical and anatomical variables. Materials and methods: The prospective study consisted of 544 images (375 pre-treatment CBCT and 169 post-treatment CBCT) from 15 prostate adenocarcinoma patients that were used for intrafractional prostate motion determination. In addition, two radiation oncologists re-contoured the bladder and rectum on each CBCT according to the patient's anatomy of the day. ANOVA and correlation analysis followed by linear regression analysis were performed to identify clinical or anatomical variables that predict large prostate intrafractional motion. Results: Prostate shift increased in patients with hormone therapy (p ≤ 0.02). The regression analysis showed that patients with large bladder intrafractional filling (p < 0.01) and a large bladder volume difference from planning CT were more likely to experience bigger longitudinal prostate motion (> 3 mm). Recommended bladder size values: anterior–posterior size ≤ 10 cm and anterior–posterior/cranio-caudal ratio ≤ 1.7, both parameters measured in the midsagittal prostate plane, were defined. Conclusions: The treatment margin should not be reduced for those patients who were treated with hormone therapy and/or whose rectum or bladder was far from complying the preparation protocol conditions. [ABSTRACT FROM AUTHOR]

Resumen Introducción Los objetivos del trabajo son caracterizar las propiedades de la imagen 2 D PET reconstruida mediante el algoritmo ordered-subset expectation maximization (OSEM) y proponer un nuevo método de generación de imágenes sintéticas. Material y métodos El ruido se analiza en términos de magnitud, correlación espacial y distribución espectral a través de la desviación estándar, la función de autocorrelación y el espectro de potencias de ruido (NPS, por noise power spectrum), respectivamente. También se estudian sus variaciones con la posición y la cantidad de actividad. Este análisis del ruido se realiza sobre imágenes de maniquí a partir de distribuciones de actividad de 18 F homogéneas. Para estudiar la resolución espacial del sistema a través de la point spread function (PSF) se emplean los coeficientes de recuperación medidos en esferas calientes en diferentes entornos radiactivos. Las funciones PSF y NPS proporcionan la base del método de simulación propuesto: convolución con la PSF como núcleo y adición de ruido a partir del NPS. Resultados El análisis del ruido espectral muestra que la principal contribución es de naturaleza aleatoria. También se observa que la corrección de atenuación no altera la textura del ruido pero sí modifica su magnitud. Finalmente, las imágenes sintéticas de 2 maniquíes, uno de ellos un cerebro anatómico, son comparadas cuantitativamente con las imágenes experimentales, encontrando un buen acuerdo en términos de valores de píxel y correlaciones entre píxeles. Así, la razón contraste-ruido para la esfera más grande del maniquí NEMA IEC es 10,7 en la imagen sintética y 8,8 en la imagen experimental. Conclusiones Las propiedades de las imágenes PET-OSEM pueden ser descritas por las funciones NPS y PSF. Las imágenes simuladas, incluyendo regiones anatómicas, son generadas satisfactoriamente mediante el método propuesto basado en las funciones NPS y PSF. Introduction The goals of the study are to characterize imaging properties in 2 D PET images reconstructed with the iterative algorithm ordered-subset expectation maximization (OSEM) and to propose a new method for the generation of synthetic images. Material and methods The noise is analyzed in terms of its magnitude, spatial correlation, and spectral distribution through standard deviation, autocorrelation function, and noise power spectrum (NPS), respectively. Their variations with position and activity level are also analyzed. This noise analysis is based on phantom images acquired from 18 F uniform distributions. Experimental recovery coefficients of hot spheres in different backgrounds are employed to study the spatial resolution of the system through point spread function (PSF). The NPS and PSF functions provide the baseline for the proposed simulation method: convolution with PSF as kernel and noise addition from NPS. Results The noise spectral analysis shows that the main contribution is of random nature. It is also proven that attenuation correction does not alter noise texture but it modifies its magnitude. Finally, synthetic images of 2 phantoms, one of them an anatomical brain, are quantitatively compared with experimental images showing a good agreement in terms of pixel values and pixel correlations. Thus, the contrast to noise ratio for the biggest sphere in the NEMA IEC phantom is 10.7 for the synthetic image and 8.8 for the experimental image. Conclusions The properties of the analyzed OSEM-PET images can be described by NPS and PSF functions. Synthetic images, even anatomical ones, are successfully generated by the proposed method based on the NPS and PSF. [ABSTRACT FROM AUTHOR]

Background/purpose: To evaluate the impact of intensity-modulated radiotherapy (IMRT) with intra-prostate fiducial markers image-guided radiotherapy (IGRT) on the incidence of late urinary toxicity compared to 3D conformal radiotherapy (3DCRT) for patients with prostate cancer (PC). Methods and materials: We selected 733 consecutive patients with localized PC treated with dose-escalation radiotherapy between 2001 and 2014. Eligibility criteria were radiation dose >72.0 Gy, no pelvic RT and minimum follow-up 24 months. 438 patients were treated with 3DCRT and 295 with IMRT. Acute and late urinary complications were assessed using the EORTC/RTOG and CTCAEs v3.0 definition. The Cox regression model was used to compare grade ≥2 urinary toxicity between both techniques. The median follow-up was 75 months (range 24-204). Results: The median isocenter radiation dose was 78.7 Gy for 3DCRT and 80.7 Gy for IMRT/IGRT ( p < 0.001). The 5-year incidence of late grade ≥2 urinary toxicity was 6.4% for IMRT and 10.8% for 3DCRT [hazard ratio (HR) 0.575, p = 0.056]. The corresponding 5-year estimates of late grade ≥2 hematuria were 2% for IMRT and 5.3% for 3DCRT (HR 0.296, p = 0.024). On multivariate analysis, the antecedent of prior transurethral resection of the prostate was also a strong predictor of a higher risk of urinary complications (HR 2.464, p = 0.002) and of hematuria (HR 5.196, p < 0.001). Conclusion: Compared with 3DCRT, high-dose IMRT/IGRT is associated with a lower rate of late urinary complications in spite of higher radiation dose. [ABSTRACT FROM AUTHOR]

Molecular transistor is a good candidate as substitute of CMOS device due to small size, expected good performance and suitability to be included in high densitycircuits. To date a lot of effort has been carried out to understand the conduction properties in molecular devices. However, minor effort has been devoted to reduce their computational complexity to obtain a compact molecular model. First-principle based methods frequently used are highly computational demanding for a single device, thus they are not suitable for complex circuit design. In this paper we present an accurate and at the same time computationally efficient method (named Efficient and Effective model based on Broadening level, Evaluation of peaks, SCF and discrete levels, ee-besd) to calculate the electron transport characteristics of molecular transistors in presence of applied bias and gate voltages. The results obtained show a remarkable improvement in terms of computational time with respect to existing approaches, while maintaining a very good accuracy. Finally, the ee-besd model has been embedded in a circuit level simulator in order to showits functionalities and, particularly, its computational cost. This is shown to be affordable even for circuits based on a high number of devices. [ABSTRACT FROM AUTHOR]

Summary: The aim of this study was to investigate vitamin D status and stress fracture risk during Royal Marine military training. Poor vitamin D status was associated with an increased risk of stress fracture. Vitamin D supplementation may help to reduce stress fracture risk in male military recruits with low vitamin D status. Introduction: Stress fracture is a common overuse injury in military recruits, including Royal Marine (RM) training in the UK. RM training is recognised as one of the most arduous basic training programmes in the world. Associations have been reported between serum 25-hydroxyvitamin D (25(OH)D) and risk of stress fracture, but the threshold of 25(OH)D for this effect remains unclear. We aimed to determine if serum 25(OH)D concentrations were associated with stress fracture risk during RM training. Methods: We prospectively followed 1082 RM recruits (males aged 16-32 years) through the 32-week RM training programme. Troops started training between September and July. Height, body weight and aerobic fitness were assessed at week 1. Venous blood samples were drawn at weeks 1, 15 and 32. Serum samples were analysed for 25(OH)D and parathyroid hormone (PTH). Results: Seventy-eight recruits (7.2 %) suffered a total of 92 stress fractures. Recruits with a baseline serum 25(OH)D concentration below 50 nmol L had a higher incidence of stress fracture than recruits with 25(OH)D concentration above this threshold (χ = 3.564, p = 0.042; odds ratio 1.6 (95 % confidence interval (CI) 1.0-2.6)). Baseline serum 25(OH)D varied from 47.0 ± 23.7 nmol L in February, to 97.3 ± 24.6 nmol L in July (overall mean 69.2 ± 29.2 nmol L, n = 1016). There were weak inverse correlations between serum 25(OH)D and PTH concentrations at week 15 ( r = −0.209, p < 0.001) and week 32 (r = −0.214, p < 0.001), but not at baseline. Conclusion: Baseline serum 25(OH)D concentration below 50 nmol L was associated with an increased risk of stress fracture. Further studies into the effects of vitamin D supplementation on stress fracture risk are certainly warranted. [ABSTRACT FROM AUTHOR]

Deep convection is one of various complex processes driving the evolution of tropical cyclones (TCs). The scales associated with deep convection are too small to be resolved by global NWP models. In the deep convection parameterization used by the Canadian Global Deterministic Prediction System (GDPS), the trigger function depends on various criteria, one of which is the adjustable 'trigger velocity' parameter, a vertical velocity threshold used in the parcel stability test of the scheme. In this study, the sensitivity of the GDPS TC activity and precipitation distribution to convective triggering parameters is investigated by varying this threshold. Multiple basins are considered for three TC seasons, and the impacts of trigger velocity variations on TC statistics (forecast hits, bias, false alarms, and track and intensity errors) and on the model's genesis potential index (GPI) are measured. It is shown that a reduction of the trigger velocity, from 0.05 to 0.01 m s−1, over the tropical oceans leads to increased convective stabilization of atmospheric columns, as well as an increase in convective precipitation amounts but a reduction in total (subgrid plus grid scale) precipitation accumulations. The trigger adjustment also yields a significant reduction of TC false alarm ratios, with no impact on forecast mean errors for true cyclones other than an expected deterioration of the intensity bias, and a systematic reduction of the average GPI over various basins at all lead times. A conceptual model is proposed to explain the relation between trigger adjustments and TC development. [ABSTRACT FROM AUTHOR]

A stereotactic brain biopsy system that is magnetic resonance ( MR) imaging-guided has not been validated in dogs. Our purpose was to determine the mean needle placement error in the caudate nucleus, thalamus, and midbrain of a canine cadaver brain using the modified Brainsight™ stereotactic system. Relocatable reference markers (fiducial markers) were attached to the cadaver head using a dental bite block. A T1-weighted gradient echo three-dimensional (3 D) sequence was acquired using set parameters. Fiducial markers were used to register the head to the acquired MR images in reference to a 3 D position sensor. This allowed the planning of trajectory path to brain targets in real time. Coordinates ( X, Y, Z) were established for each target and 0.5 μl of diluted gadolinium was injected at each target using a 26-gauge needle to create a lesion. The center of the gadolinium deposition was identified on the postoperative MR images and coordinates ( X′, Y′, Z′) were established. The precision of this system in bringing the needle to target (needle placement error) was calculated. Seventeen sites were targeted in the brain. The mean needle placement error for all target sites was 1.79 ± 0.87 mm. The upper bound of error for this stereotactic system was 3.31 mm. There was no statistically significant relationship between needle placement error and target depth ( P = 0.23). The ease of use and precision of this stereotactic system support its development for clinical use in dogs with brain lesions >3.31 mm. [ABSTRACT FROM AUTHOR]

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The current study analyzed the relationship between text comprehension and memory skills in preschoolers. We were interested in verifying the hypothesis that memory is a specific contributor to listening comprehension in preschool children after controlling for verbal abilities. We were also interested in analyzing the developmental path of the relationship between memory skills and listening comprehension in the age range considered. Forty-four, 4-year-olds (mean age = 4 years and 6 months, SD=4 months) and 40, 5-year-olds (mean age = 5 years and 4 months, SD=5 months) participated in the study. The children were administered measures to evaluate listening comprehension ability (story comprehension), short-term and working memory skills (forward and backward word span), verbal intelligence and receptive vocabulary. Results showed that both short-term and working memory predicted unique and independent variance in listening comprehension after controlling for verbal abilities, with working memory explaining additional variance over and above short-term memory. The predictive power of memory skills was stable in the age range considered. Results also confirm a strong relation between verbal abilities and listening comprehension in 4- and 5-year-old children. [ABSTRACT FROM AUTHOR]

The relation between text and idiom comprehension in children with poor text comprehension skills was investigated longitudinally. In the first phase of the study, six-year-old first graders with different levels of text comprehension were compared in an idiom and sentence comprehension task. Text comprehension was shown to be more closely related to idiom comprehension than sentence comprehension. The follow-up study, carried out eight months later on less-skilled text comprehenders, investigated whether an improvement in text comprehension was paralleled by an improvement in idiom comprehension. The development of sentence comprehension was also taken into account. Children who improved in text comprehension also improved in idiom comprehension; this improvement was, instead, weakly related to an improvement in sentence comprehension. The relationship between text and idiom comprehension is discussed in the light of the Global Elaboration Model (Levorato & Cacciari, 1995). [ABSTRACT FROM AUTHOR]

Objective: Movements of brain tissue during neurosurgical procedures reduce the effectiveness of using pre-operative images for intra-operative surgical guidance. In this paper, we explore the use of acquiring intra-operative ultrasound (US) images for the quantification of and correction for non-linear brain deformations. Materials and Methods: We will present a multi-modal registration strategy that automatically matches pre-operative images (e.g., MRI) to intra-operative US to correct for these deformations. The strategy involves using the predicted appearance of neuroanatomical structures in US images to build “pseudo ultrasound” images based on pre-operative segmented MRI. These images can then be non-linearly registered to intra-operative US using cross-correlation measurements within the ANIMAL package. The feasibility of the theory is demonstrated through its application to clinical patient data acquired during 12 neurosurgical procedures. Results: Results of applying the method to 12 surgical cases, including those with brain tumors and selective amygdalo-hippocampectomies, indicate that our strategy significantly recovers from non-linear brain deformations occurring during surgery. Quantitative results at tumor boundaries indicate up to 87% correction for brain shift. Conclusions: Qualitative and quantitative examination of the results indicate that the system is able to correct for non-linear brain deformations in clinical patient data. [ABSTRACT FROM AUTHOR]

Ofloxacin (OFX) is a fluorquinolone characterized by photochemical instability. With the goal to improve its photostability in aqueous solutions, the complexation of ofloxacin with β-cyclodextrin was investigated. The complexes showed a water solubility enhancement of approximately 2.6 times; nevertheless, the photodegradation of ofloxacin was not reduced. The complexes obtained were characterized by thermal and [SUP1]H nuclear magnetic resonance (NMR) analysis, which revealed an interaction between ofloxacin and β-cyclodextrin. The last analysis indicated that only parial inclusion of the N-methylpiperazinyl moiety occurred, which can explain the fact that photostabilization was not improved. This partial inclusion phenomenon could be explained also by computer-aided molecular modeling. [ABSTRACT FROM AUTHOR]

1996 wurden zur Beurteilung der Immunitätslage der sächsischen Bevölkerung gegen Diphtherie 1378 Seren von Personen untersichiedlichen Alters im Zellkulturtest nach Miyamura auf neutralisierende Diphtherie-Antitoxingehalte untersucht (immunitätskataster). An 203 Personen, bei denen eine Indikation zur Wiederimpfung vorlag, wurde die Boosterfähigkeit in Abhängigkeit von der dokumentierten Grundimmunisierung, der Anzahl der Widerimpfungen und nach dem Abstand zur letzten Impfung mit der gleichen Methodik beurteilt. Die Erfassung der diesbezüglich notwendigen personenbezogenen Angaben, die Serumgewinnung und Impfdurchführung erfolgte durch die Gesundheitsämter nach einem vorgegebenen Programm. Die Immunitätslage der Bevölkerung Sachsens, wohl stellvertretend für alle neuen Bundesländer, ist dank der 1961–1990 praktizierten Pflichtimpfung 1996 insgesamt noch mit ausreichend gut zu bewerten: 70% waren sicher, 17,7% relativ und nur 12,3% nicht geschützt. Unbefriedigend ist die Immunitätslage bei den über, 40jährigen. Eine Boosterfähigkeit ist in Abhängigkeit von der dokumentierten Grundimmunisierung unterschiedlich zu beurteilen. Auch bei Jahrzehnte zurückliegender vollständiger und dokumentierter Grundimmunisierung reicht eine einmalige Boosterimpfung aus, um einen vollständigen Impfschutz zu induzieren. Nicht so bei unbekannter, aus dem Gedächtnis benannter, Impfanamnese. Hier ist eine Vervollständigung der Grundimmunisierung zwingend erforderlich. In 1996, 1378 sera of persons of different age were examined for neutralizing diphtheria antitoxin levels by the cell culture test according to Miyamura to evaluate the diphtheria immunity situation among the population in Saxony (immunity register). In 203 persons in which revaccination was indicated, the booster capacity has been evaluated by the same method based on the documented basic immunization, the number of revaccinations and the time which had passed since the last vaccination. Recording of the respective personal data, serum production and vaccination were performed by the public health departments according to a specific programme. The overallimmunity situation among the population in Saxony which is presumably representative of all new Federal Länder was rated as still sufficient due to compulsory vaccination that had been performed between 1961 and 1990: 70% showed sufficient, 17.7% a relative and only 12.3% no protection. The immunity situation in persons above 40 years of age was unsatisfactory. Whether there is a booster capacity will depend on the documented basic immunization. A single booster vaccination is sufficient in order to induce complete protection, even if the complete and documented basic immunization took place decades ago. This is not the case when the vaccination history has been recalled by vacciness from their personal memory. In this case, completion of basic immunization is an absolute necessity. [ABSTRACT FROM AUTHOR]

Concentrations of zinc and copper in a series of large oligotrophic lakes on Vancouver Island, Canada, have been increasing since mining operations began near the south end of Buttle lake in 1966. Declines in species diversity of both phytoplankton and periphyton have occurred since the beginning of mining activity with the disappearance of metal sensitive forms such as Asterionella and Rhizosolenia. Cladoceran and calanoid copepod numbers and species diversity increase as the metal concentrations decline downstream from the mine. Bioassays carried out with Daphnia pulex show increasing toxicity downstream. Metal concentrations in Zooplankton and metallothionein concentrations in rainbow trout liver are correlated to metal concentrations in the water. The water was not acutely toxic to rainbow trout in laboratory simulations of Buttle Lake conditions or during in situ exposures (1 month). Specific sublethal deleterious effects have not yet been determined. [ABSTRACT FROM AUTHOR]

Background: Serum insulin-like growth factor-1 (IGF-1) exists as ternary and binary complexes, and as the free hormone. An immunometric assay for 'free IGF-1' or 'easily dissociable IGF-1' has been described, although its use has not been widely assessed. Methods: The assay was assessed using the serum concentration/dilution test and by determining the relationship of the measured free hormone to the total hormone/binding protein ratio. Results: In six serum pools the measured free IGF-1 did not remain constant on concentration/dilution of the sample. However there was a significant correlation between the measured free IGF-1 and total IGF-1 (P < 0·001) and between total IGF-1/IGF binding protein-3 ratio (P < 0·001). Discussion: Although the assay failed the serum concentration/dilution test, there was still a significant relationship to the total hormone/binding protein ratio. It is possible that the serum dilution test is inappropriate to such a complex system or that the assay does not measure the free fraction. It is suggested that, though more cumbersome, it should be referred to as 'easily dissociable' IGF-1 as suggested by the manufacturers. [ABSTRACT FROM AUTHOR]

A simple and effective technique to skip the computation of reliable portions of a frame (windows) for turbo code decoding is proposed. The proposed criterion relies on a very simple approximation of cross-entropy measure by means of thresholding. This criterion features negligible complexity and low-memory requirements. Simulation results show that, in the best case, up to 20% of windows can be skipped with no error-rate degradation. Such a significant computation reduction can be exploited to directly reduce the power consumption as well. [ABSTRACT FROM AUTHOR]